Abstract:

Throughout life, different types of stem cells participate in tissue generation, maintenance,
plasticity, and repair. Their abilities to secrete growth factors, to proliferate and differentiate into several
cell lineages, and to migrate and home into the damaged tissues have made them attractive candidates for
cell therapy and tissue engineering applications. Normal stem cell function is tied to the cell-intrinsic
mechanisms and extrinsic signals derived from the surrounding microenvironment or circulation. Understanding
the regulatory signals that govern stem cell functions is essential in order to have full knowledge about organogenesis,
tissue maintenance and tissue plasticity in the physiological condition. It is also important for optimizing tissue engineering
and improving the therapeutic efficiency of stem cells in regenerative medicine. A growing body of evidence indicates
that hormonal signals can critically influence stem cell functions in fetal, postnatal, and adult tissues. This review focuses on
recent studies revealing how growth hormone, insulin, thyroid hormone, parathormone, adrenocorticotropin, glucocorticoids,
erythropoietin, and gastrointestinal hormones control stem cell behavior through influencing survival, proliferation, migration,
homing, and differentiation of these cells. Moreover, how environmental factors such as exercise, hypoxia, and nutrition
might affect stem cell functions through influencing the endocrine system is discussed. Some of the current limitations of cell
therapy and how hormones can help overcoming these limitations are briefly outlined.

Abstract:Throughout life, different types of stem cells participate in tissue generation, maintenance,
plasticity, and repair. Their abilities to secrete growth factors, to proliferate and differentiate into several
cell lineages, and to migrate and home into the damaged tissues have made them attractive candidates for
cell therapy and tissue engineering applications. Normal stem cell function is tied to the cell-intrinsic
mechanisms and extrinsic signals derived from the surrounding microenvironment or circulation. Understanding
the regulatory signals that govern stem cell functions is essential in order to have full knowledge about organogenesis,
tissue maintenance and tissue plasticity in the physiological condition. It is also important for optimizing tissue engineering
and improving the therapeutic efficiency of stem cells in regenerative medicine. A growing body of evidence indicates
that hormonal signals can critically influence stem cell functions in fetal, postnatal, and adult tissues. This review focuses on
recent studies revealing how growth hormone, insulin, thyroid hormone, parathormone, adrenocorticotropin, glucocorticoids,
erythropoietin, and gastrointestinal hormones control stem cell behavior through influencing survival, proliferation, migration,
homing, and differentiation of these cells. Moreover, how environmental factors such as exercise, hypoxia, and nutrition
might affect stem cell functions through influencing the endocrine system is discussed. Some of the current limitations of cell
therapy and how hormones can help overcoming these limitations are briefly outlined.